Method of treating aluminum silicate.



reduced. By increasin UNITED STAT'Esi orrrcn FRANK TONE, or NmeARA FALns', NEW YoRK; AssIGNoR TO THE GARBORUNDUM COMPANY, or NIAGARA FALLS, EW YORK, AcoR'PoRA'r'Io'N OF PENNSY VANIA.

MfiTHOD osrsm'rme SILiGATE.

specification of Letters Patent.

Patented'D'ec. 8, 1908.

Application-filed much 17-, 190a Serial No. 421,731.

I '0 all whom it mag concern:

Be it known that I, FRANK J. ToNE, of Niagara Falls, Niagara county, New York, have invented a new and useful Method of Treating Aluminum Silicate, of which the following is a full, clear, and exact description.

The invention refers to the reduction of aluminum ores, particularly to aluminum silicate, and has for its object the production therefrom of new anduseful substances containing aluminum and silicon.

Aluminum silicate is an ore of aluminum of wide occurrence and is the basis of all true clays. I have discovered that by smelting this ore in the electric furnace together with a suitable reducing" agent in proper amount, it ispossible to reduce the silicon without reducing the aluminum,- and furthermore that by proplortioning" the amount of reducing agent so t 'at it shall be insuflicient to reduce all the silicon, it is possible to make a fractional reduction of the silicon to any desired amount, leaving all the alumina and part of the silica unrcduced. I have also discovered that by pro er regulation of temperature I amable to filse the residuum of alumina and slllca into a homogeneous material having great hardness andvaluable abrasive and refrac tory qualities. As an example of one method of carrying out this process I take any form of aluminum silicate, such as kaolin, pref erably first calcining it to drive off the combinedwater. I mix with the kaolin a reducing agent such as carbon, in the proportions indicated by the following equation:

When this charge is smelted in the electric furnace the carbon reduces a proximately the theoretical amount of si icon oxid to silicon, and there remains alumina and silica in about the proportions of 77 er cent. alumina and 23 per cent silica. ith the proper regulation of temperature these two compounds are fused into a homogeneous material, this fusion being carried out at the same time that the silicon is being the amount of carbon in the mixture it is possible to reduce a greater proportion of the silicon and leave an alumina-silica residuum having a lower content of silica than shown in equation 2. e A1,o,.2sio, 220+ 1 1Fe eA1,o Si0,,) 1 1FeSi+ 2200 there is obtained an iron silicid having a content of 33 er" cent. silicon and a fused residuum of a u'minaand. silica. containing about 9- per. cent.- of silica.

-Any ordinary formof are furnacewithvertical' electrodes dependinginto the furnacelpot or chamber is suitable for carryin out t is process. The charge mixture is feil into the furnace around the electrodes, and as the finished product accumulates and builds up under the arc the electrodes are raised to allow the finished product to form a pig. or ingot of considerable size. After a sufiicient amount of mixture has been smelted to form an ingot of a size convenient to handle, the furnace runis sto ped and the fused mass is allowed. to cooll silicid being heavier than the aluminarsilica material, has atendency to settle to the bot tom ofthe furnace from which it may be tapped at intervals during the run. By carrying the temperature sufiiciently high, it is possible also to tap out the aluminasilica material together with the iron silicid, and by adding fresh charge from time to time to carry on the recess substantially continuously. When the two materials are tap ed out together the iron silicid settles in the ottom of the ladle and, after cooling is easily separated from the alumina-silica material. Small portions of the silicon alloy scattered through the fused material may be separated therefrom by concentration, after the latter is crushed. The separation'may also be facilitated during the crushing if the silicon and base metal are combined in the alloy in proper proportion to form a disintegrating alloy. I have found that by taking the base metalliferous material as manganese or manganese ore, in proportions to form a The iron of similar character.

silicid containing 45 to 55 per cent. manganese, the allo is friable and on exposure to air tends to isintegrate into a fine powder. An iron silicid containing 35 per cent. iron is Other disintegrating alloys may be produced in similar manner and for the same purpose of facilitating separation of finished roducts.

The silicids pro uced in this process are useful for various purposes such as the refining of iron and steel. The fused aluminasilica material has a hardness equal to man grades of corundum, and is very-tough. t is therefore valuable as an abrasive. It is also very refractory. When it is tapped from the furnace it may be cast into mo ds. It is possible to vary its (tualities such as hardness and toughness, y varying the ratio of silica and alumina, and I have found that these valuable roperties are possessed by the material w e-its silica content varies between five and thirty-five per; cent. Basic and other impurities are substantially absent.

I claim:

1. The hereindescribed method of treating aluminum silicate, which consists in mixing with it an amount of carbon msuflicient to reduce all the silicon, and subjecting the mixture to electrically developed heat sufficient to reduce a portion of the silicon and to fuse the alumina-silica residuum into a hard refractory abrasive material.

2. The herein described method of treating aluminum silicate, which consists in mixing with it an amount of carbon insufiiclent to reduce all the silicon, subjectingthe mixture to electrically developed.heat suflicient to reduce a portion of the silicon and to fuse the alumina-silica residuum into a hard refractory abrasive material, and separating the silicon from the alumina-silica material.

3. The herein described method of treating aluminum silicate, which consists in making a mixture of aluminum silicate, carbon, and base metalliferous material, the amount of carbon being insufiicient to reduce all the silicon, subjecting said mixture to electrically developed heat sufiicientto reduce a portion of the silicon and combine it with the base metal, the amount of said silicon reduced being determined by the amount of carbon present, and to fuse the aluminasilica residuum.

4. The herein described method of treating aluminum silicate, which consists in mak inga mixture of aluminum silicate, carbon,- and base metalliferous material, the amount of carbon being insufficient to reduce all the silicon, subjecting said mixture -to electrically developed heat sufiicient to reduce a portion of the silicon and combine it with the base metal, the amount of said silicon reduced being determined by the amount of carbon present, to fuse the alumina-silica residuum, and allowing the products to cool and then separating the products.

5. The herein described method of treating aluminum silicate, which consists in making a mixture of aluminum silicate, carbon, and base metalliferous material, the amount of carbon being insufficient to reduce all the silicon, subjecting said mixture to electrically developed heat sufiioient to reduce a portion of the silicon and combine it with the base metal, the amount of said silicon reduced being determined by the amount of carbon present, and to fuse the alumina silica residuum, tapping the products from the furnace, allowing them to cool, and separating them.

6. The herein describedmethod of treating aluminum silicate, which consists in mak ing a mixture of aluminumsilicate, carbon, and base metalliferous material, the amount of carbon being insufficient to reduce all the silicon, subjecting said mixture to electrically developed heat sufiicient to reduce a portion of the silicon and combine it with the base metal, the amount of said silicon re-.

duced being determined by the amount of carbon present, and to fuse the alumina silica residuum, tap ing the said residuum from the furnace and casting it in molds.

7. Theherein described method of treating aluminum silicate, which consists in making a mixture of aluminum silicate, carbon, and base metalliferous material, the amount of carbon being insufficient to reduce all the silicon, and the amount of base metalliferous material being suflioient to form a disintegrating alloy with the reduced silicon, and subjecting said mixture to electrically developed heat sufficient to reduce a portlon of the silicon and combine it with the base metal and to fuse the alumina-silica residuum.

In testimony whereof, I have hereunto set my hand.

FRANK J. TONE; Witnesses:

FRED I. PIERCE, CHARLES CHQRMANN. 

